// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_FRAME_HOST_NAVIGATOR_DELEGATE_H_
#define CONTENT_BROWSER_FRAME_HOST_NAVIGATOR_DELEGATE_H_

#include "base/strings/string16.h"
#include "content/public/browser/invalidate_type.h"
#include "content/public/browser/navigation_controller.h"
#include "content/public/browser/navigation_throttle.h"
#include "content/public/browser/navigation_ui_data.h"
#include "content/public/browser/reload_type.h"
#include "ui/base/page_transition_types.h"
#include "ui/base/window_open_disposition.h"

class GURL;
struct FrameHostMsg_DidCommitProvisionalLoad_Params;

namespace content {

class FrameTreeNode;
class NavigationHandle;
class RenderFrameHostImpl;
struct LoadCommittedDetails;
struct OpenURLParams;

// A delegate API used by Navigator to notify its embedder of navigation
// related events.
class CONTENT_EXPORT NavigatorDelegate {
public:
    // Called when a navigation started. The same NavigationHandle will be
    // provided for events related to the same navigation.
    virtual void DidStartNavigation(NavigationHandle* navigation_handle) { }

    // Called when a navigation was redirected.
    virtual void DidRedirectNavigation(NavigationHandle* navigation_handle) { }

    // Called when the navigation is about to be committed in a renderer.
    virtual void ReadyToCommitNavigation(NavigationHandle* navigation_handle) { }

    // Called when the navigation finished: it was either committed or canceled
    // before commit.  Note that |navigation_handle| will be destroyed at the end
    // of this call.
    virtual void DidFinishNavigation(NavigationHandle* navigation_handle) { }

    // TODO(clamy): all methods below that are related to navigation
    // events should go away in favor of the ones above.

    // The RenderFrameHost started a provisional load for the frame
    // represented by |render_frame_host|.
    virtual void DidStartProvisionalLoad(RenderFrameHostImpl* render_frame_host,
        const GURL& validated_url,
        bool is_error_page) { }

    // A provisional load in |render_frame_host| failed.
    virtual void DidFailProvisionalLoadWithError(
        RenderFrameHostImpl* render_frame_host,
        const GURL& validated_url,
        int error_code,
        const base::string16& error_description,
        bool was_ignored_by_handler) { }

    // Document load in |render_frame_host| failed.
    virtual void DidFailLoadWithError(
        RenderFrameHostImpl* render_frame_host,
        const GURL& url,
        int error_code,
        const base::string16& error_description,
        bool was_ignored_by_handler) { }

    // A navigation was committed in |render_frame_host|.
    virtual void DidCommitProvisionalLoad(
        RenderFrameHostImpl* render_frame_host,
        const GURL& url,
        ui::PageTransition transition_type) { }

    // Handles post-navigation tasks in navigation BEFORE the entry has been
    // committed to the NavigationController.
    virtual void DidNavigateMainFramePreCommit(bool navigation_is_within_page) { }

    // Handles post-navigation tasks in navigation AFTER the entry has been
    // committed to the NavigationController. Note that the NavigationEntry is
    // not provided since it may be invalid/changed after being committed. The
    // NavigationController's last committed entry is for this navigation.
    virtual void DidNavigateMainFramePostCommit(
        RenderFrameHostImpl* render_frame_host,
        const LoadCommittedDetails& details,
        const FrameHostMsg_DidCommitProvisionalLoad_Params& params) { }
    virtual void DidNavigateAnyFramePostCommit(
        RenderFrameHostImpl* render_frame_host,
        const LoadCommittedDetails& details,
        const FrameHostMsg_DidCommitProvisionalLoad_Params& params) { }

    virtual void SetMainFrameMimeType(const std::string& mime_type) { }
    virtual bool CanOverscrollContent() const;

    // Notification to the Navigator embedder that navigation state has
    // changed. This method corresponds to
    // WebContents::NotifyNavigationStateChanged.
    virtual void NotifyChangedNavigationState(InvalidateTypes changed_flags) { }

    // Notifies the Navigator embedder that a navigation to the pending
    // NavigationEntry has started in the browser process.
    virtual void DidStartNavigationToPendingEntry(const GURL& url,
        ReloadType reload_type) { }

    // Opens a URL with the given parameters. See PageNavigator::OpenURL, which
    // this forwards to.
    virtual void RequestOpenURL(RenderFrameHostImpl* render_frame_host,
        const OpenURLParams& params) { }

    // Returns whether to continue a navigation that needs to transfer to a
    // different process between the load start and commit.
    virtual bool ShouldTransferNavigation(bool is_main_frame_navigation);

    // Returns whether URLs for aborted browser-initiated navigations should be
    // preserved in the omnibox.  Defaults to false.
    virtual bool ShouldPreserveAbortedURLs();

    // A RenderFrameHost in the specified |frame_tree_node| started loading a new
    // document. This correponds to Blink's notion of the throbber starting.
    // |to_different_document| will be true unless the load is a fragment
    // navigation, or triggered by history.pushState/replaceState.
    virtual void DidStartLoading(FrameTreeNode* frame_tree_node,
        bool to_different_document) { }

    // A document stopped loading. This corresponds to Blink's notion of the
    // throbber stopping.
    virtual void DidStopLoading() { }

    // The load progress was changed.
    virtual void DidChangeLoadProgress() { }

    // Returns the NavigationThrottles to add to this navigation. Normally these
    // are defined by the content/ embedder, except in the case of interstitials
    // where no NavigationThrottles are added to the navigation.
    virtual std::vector<std::unique_ptr<NavigationThrottle>>
    CreateThrottlesForNavigation(NavigationHandle* navigation_handle);

    // PlzNavigate
    // Called at the start of the navigation to get opaque data the embedder
    // wants to see passed to the corresponding URLRequest on the IO thread.
    // In the case of a navigation to an interstitial, no call will be made to the
    // embedder and |nullptr| is returned.
    virtual std::unique_ptr<NavigationUIData> GetNavigationUIData(
        NavigationHandle* navigation_handle);
};

} // namspace content

#endif // CONTENT_BROWSER_FRAME_HOST_NAVIGATOR_DELEGATE_H_
